RESUMEN
Abstract Background Oligoclonal bands (OCBs) and Kappa free light chains (FLCs) in the cerebrospinal fluid (CSF) are sensitive markers of intrathecal immunoglobulin (Ig)G synthesis in patients with multiple sclerosis. Objective To evaluate the concordance rate between OCBCs and the Kappa index (KI) in patients with suspected multiple sclerosis (MS). Methods Patients with suspected MS were referred to a specialized CSF laboratory as part of their diagnostic investigation. Paired CSF and serum samples were collected and submitted to detection of OCBs and determination of the KI. Positive and negative results were determined with both methods, and the percentage of agreement between them was established. Results In total, 171 serum and CSF samples from 171 patients were included in the analysis. The mean age of the patients was of 40 ± 14.2 years; 18.9% of them were male, and 81.1% were female. The OCBs and KI presented concordant results in 161 (94.2%) samples: in 74 (43.3%), both were positive, and in 87 (50.9%), both were negative. In 10 cases, the results were discrepant: KI positive/OCB negative in 8 and OCB positive/KI negative in 2 cases. Conclusion The KI and OCBs presented high concordance level. Currently, the detection of OCBs in the CSF is the standard method for MS diagnosis, but it is time-consuming, and its visual interpretation can be difficult. The results suggest that the KI is a good alternative for the detection of intrathecal immunoproduction in cases of suspected MS.
Resumo Antecedentes Bandas oligoclonais (BOCs) e cadeias leves de imunoglobulina (free light chains, FLCs, em inglês) Kappa no líquido cefalorraquidiano (LCR) são marcadores sensíveis da síntese intratecal de imunoglobulina (Ig)G em pacientes com esclerose múltipla (EM). Objetivo Avaliar a taxa de concordância entre BOCs e o índice Kappa (IK) em pacientes com suspeita de EM. Métodos Pacientes com suspeita de EM foram encaminhados a um laboratório especializado em LCR como parte de sua investigação diagnóstica. Amostras pareadas de LCR e soro foram coletadas e investigadas quanto à presença de BOCs e submetidas à determinação do IK. Resultados positivos e negativos foram determinados com ambos os métodos, e estabeleceu-se o percentual de concordância entre eles. Resultados Ao todo, 171 amostras de soro e LCR de 171 pacientes foram incluídas na análise. A média de idade dos pacientes foi de 40 ± 14,2 anos; 18,9% deles eram do sexo masculino, e 81,1%, do sexo feminino. Resultados concordantes entre as BOCs e o IK foram observados em 161 (94,2%) amostras: em 74 (43,3%), ambos foram positivos, e em 87 (50,9%), ambos foram negativos. Em 10 casos, os resultados foram discrepantes: IK positivo/BOC negativo em 8, e BOC positivo/IK negativo em 2. Conclusão Observou-se alto nível de concordância entre o IK e as BOCs. A detecção de BOCs no LCR é atualmente o método padrão para o diagnóstico de EM, mas é demorado, e sua interpretação visual pode ser difícil. Os resultados sugerem que o IK pode ser uma alternativa para a detecção de imunoprodução intratecal em casos de suspeita de EM.
RESUMEN
ABSTRACT Background Neurosyphilis is difficult to be diagnosed. CSF VDRL is the gold standard, but its sensitivity is low. Cerebrospinal fluid (CSF) PCR for the detection of Treponema pallidum DNA has been evaluated; however, its diagnostic value is still poorly understood. Methods Here we performed a systematic review including articles that assessed the diagnostic sensitivity of CSF PCR in patients with syphilis and neurosyphilis. The CSF PCR sensitivity and specificity of different PCR assays was assessed in patients with neurosyphilis with or without HIV coinfection and in patients with syphilis with no central nervous system (CNS) manifestations. Results Eighteen studies evaluating 703 patients were included. The PCR sensitivity for neurosyphilis was 73.9% among HIV negative and 37.5% among HIV infected patients, having varied from 62.2% to 100% with different PCR assays. The sensitivity of CSF VDRL CSF was 68% in the same population. The specificity of CSF PCR was 93%. CSFPCR was positive in16.4% of the patients with primary and secondary syphilisand 28.9% of patients with latent syphilis. None of the syphilis cases without neurological manifestations were positive with CSF VDRL. Conclusion CSF PCR seems to be at least as sensitive as CSF VDRL, with good specificity. In addition, CSF PCR may potentially reveal early neuroinvasion in patients withsyphilis with no CNS symptoms. Future studies are still needed to assess the potential clinical value of detecting T. pallidum DNA in CSF in syphilis cases prior to the development of CNS symptoms.
RESUMEN
ABSTRACT The precise diagnosis of bacterial meningitis is essential. Cytological and biochemical examination of cerebrospinal fluid (CSF) are not specific. Conventional methods for bacterial meningitis lack sensitivity or take too long for a final result. Therefore, other methods for rapid and accurate diagnosis of central nervous system infections are required. FilmArray meningitis/encephalitis (ME) panel is a PCR multiplex for simultaneous and rapid identification of 14 pathogens, including 6 bacteria, 7 viruses, and Cryptococcus. We evaluated 436 CSF samples submitted to FilmArray ME Panel. Among them, 25 cases were positive for bacteria, being Streptococcus pneumonia the most frequent (48 %). Among positive cases for bacteria, 60 % were positive only with FilmArray. All the bacterial meningitis cases in which the only positive test was FilmArray had CSF findings suggestive of bacterial meningitis, including neutrophilic pleocytosis, increased CSF protein and lactate, and decreased CSF glucose. These findings suggest that FilmArray may increase the diagnostic sensitivity for bacterial meningitis.